Barranquitas is about one hour by winding roads from San Juan, the capital. It is nestled amid hills and mountains, and nearby, between Barranquitas and Aibonito, is located the "cañón de San Cristóbal" (Canyon of Saint Cristopher); one of the deepest canyons in the Indies. For years, the overlook was used as a municipal garbage; in the last decade, the refuse was removed and the site restored.
The town was founded in 1803 by Antonio Aponte Ramos.
Early in the 20th century, Barranquitas residents, known as Barranquiteños, had a short but legendary territory war with residents of the city of Comerío.
The Municipality of Barranquitas sits on the middle of the Cordillera Central of Puerto Rico, which is the main mountain range that crosses the island from west to east. It is bordered by the municipalities of Corozal, Naranjito, Coamo, Aibonito, Orocovis, and Comerío. Barranquitas has a surface area of 34 square miles (88.4 km2).
The terrain is mostly mountainous. Some of the peaks found in the municipality are La Torrecilla and Farallón. Barranquitas is also the site of the San Cristóbal Canyon.